The first literature of Tamil, Agathiyam was composed by Sage Agasthya who also composed thr Rig Vedic Hymns 166 to 190.
He is credited with the formal founding of the Tamil Language, which was handed over to him by Lord Shiva and Lord Subrahmanya.
Poets Conclaves were held periodically.
There were three such Conclaves,the first one was presided over by Lord Shiva at Then Madurai.( South Madurai, the present Tail Nadu city of Madurai was called Vada Madurai, North Madurai, where the last conclave of the Poets were held)
First Tamil Sangam9 First Conclave) was held at Then Madurai.
After a Tsunami, KadalKol, devoured the lands, the second Tamil Sangam was held at KavataPura, which was located south of Lanka(?).
It formed a part of the sunken continent Lemuria.
Please read my posts on Lemuria.
( Is Lemuria/Kumari Kandam the same as Atlantis?, Post follows.)
The second Sangam area was also submerged by a Tsunami and the third conclave was held at the present Madurai, Tamil Nadu.
Then we have the Tholkappiyam which follows Agathiya for Tamil works.
It is the oldest surviving Literature in Tamil.
To arrive at the dates of Tamil Sangams and the Tsunami(2) I am using the Astronomical Data mentioned in Sanskrit works,Puranas, Ramayana, Mahabharata and Tamil Classics, Silappadikaram and Manimekalai.
Agasthya’s date has been proved to be 5000 BC.
Please read my post on Agasthya Canopus validates Sanatana Dharma Tamil date.
Now taking into account the period of each Tamil Sangam, I have reworked their dates from Agasthya’s date.
The first conclave of Tamil poets took place during the Tamil Sangam which lasted 4400 years, and had 549 members,
The second conclave lasted for 3700 years and had 59 members, with 3700 poets participating.
The third Sangam lasted for 1850 years.
Agastya 5000 BC
First Sangam-5000 -4400= 600 BC
Second Sangam-600-3700=3100 AD.
* For a language to develop and to attain highly complex Grammar and Classical Literature the language should have evolved at least 1000 years earlier.
** These dates agree with the dates of Ramayana.
So Tamil language should have been used at least by 4000BC
Date of the Tsunamis, Kadalkol
Around 5000 BC
The second Tsunami,
Around 5 BC.
This is based on the Astronomical event of Canopus being visible when Agasthya traveled to South, crossing the Vindhya mountain.
This Time scale applies for the present Aeon, Kaliyuga.